Shelving and rack storage systems often provide storage space in bays positioned between vertical members. Shelves or racks may be positioned within a bay to facilitate the storage of items. Shelves and racks may be modular or otherwise designed for nonpermanent placement within a bay so that storage space may be configured and reconfigured to account for changing conditions, such as the amount of storage space required at any given time or to account for various sized packages, boxes, and articles to be stored. Modular racks and shelves are therefore often lightweight to allow for easier placement. However, strength of a shelf may be sacrificed as weight is removed.
Horizontal support structures that span the distance between vertical members are used to provide increased load bearing capacity to shelves or racks positioned within a bay. The support structures come in many forms such as tubes, channels, I-beams, and the like. As with shelves, strength of a support structure may be sacrificed as weight is removed.